More than twenty years ago, in the late 1970s and early 1980s, it was expected that non-linearities of semiconductors permit the construction of integrated low-power (μW), room temperature, and fast (picosecond; “ps”) all-optical devices. Gibbs H M, Tarng S S, Jewell J L, Weinberger D A, Tai K, Gossard A C, McCall, S L, Passner A and Wiegmann W 1982 Appl. Phys. Lett. 41 221. Specifically, nonlinear GaAs etalons appeared to be promising devices for performing optical logic operations in massively parallel architectures at rates extending into the GHz range. Jewell J L, Lee Y H, Duffy J F, Gossard A C and Wiegmann W 1986 Appl. Phys. Lett. 48 1342.
However, the “switching reality” stubbornly rejected the transformation of etalon prototypes into mass-market products since, as the main reason, the power consumption of etalons does not allow the realization of concepts with affordable power needs. After the boom surrounding all-optical computing during the mid-1980s, experts in the field have abandoned non-linear photonics for all-optical data management. Gibbs H M and Khitrova G 1990 Nonlinear Photonics ed by H M Gibbs, G Khitrova and N Peyghambarian (Berlin: Springer) p 1.
Furthermore, the ongoing fast progress in electronics requires extremely smart photonic devices in order to motivate a technology change.
Optical switching continues to play a major role in modern fiber-optic telecommunications systems. They are essential in optical add/drop, cross connect, and ring protection applications.
Nevertheless, the full application potential of semiconductors for photonics is still not fully explored and will emerge if an effective fast linear low power switch can be produced in a very simple manner.